Hello,
I need to report the status of an old piece of industrial equipment back to an input zone on a security system. The industrial equipment has a very old and propriety PLC setup and so we are actually using the status LED from the industrial machine to drive our circuit. I've soldered wires to the LED and when the LED is lit I've got 2 volts to work with.
As I'm no expert with transistors, I've looked at doing this with HFS2/A213DN solid state relay (https://www.digchip.com/datasheets/parts/datasheet/922/HFS2_A213DN-pdf.php)
I rigged up a little test and this actually works fine. The 2 volts will activate the relay and let the system know the on/off status of the LED on the machine.
My problem is that when the HFS2 relay is connected the relay doesn't illuminate. I think the SSR is simply taking too much voltage/current from the circuit and the relay.
My question is can I add a resistor and/or capacitor that might allow the SSR and the LED to work at the same time. Or should I consider a different device like a 6N138 (https://www.jaycar.com.au/medias/sys_master/images/h1c/h05/8838539739166/ZD1940-dataSheetMain.pdf
Thanks,
Paul
I need to report the status of an old piece of industrial equipment back to an input zone on a security system. The industrial equipment has a very old and propriety PLC setup and so we are actually using the status LED from the industrial machine to drive our circuit. I've soldered wires to the LED and when the LED is lit I've got 2 volts to work with.
As I'm no expert with transistors, I've looked at doing this with HFS2/A213DN solid state relay (https://www.digchip.com/datasheets/parts/datasheet/922/HFS2_A213DN-pdf.php)
I rigged up a little test and this actually works fine. The 2 volts will activate the relay and let the system know the on/off status of the LED on the machine.
My problem is that when the HFS2 relay is connected the relay doesn't illuminate. I think the SSR is simply taking too much voltage/current from the circuit and the relay.
My question is can I add a resistor and/or capacitor that might allow the SSR and the LED to work at the same time. Or should I consider a different device like a 6N138 (https://www.jaycar.com.au/medias/sys_master/images/h1c/h05/8838539739166/ZD1940-dataSheetMain.pdf
Thanks,
Paul